About Prostanthera behriana Schltdl.
Prostanthera behriana is an erect or straggling shrub that typically reaches a height of 1–2.5 meters (3 feet 3 inches to 8 feet 2 inches). It has flattened, hairy stems. Its leaves are light to mid-green, egg-shaped or reverse egg-shaped (with the narrower end toward the base), 13–26 mm long and 2–5 mm wide, and grow without a stalk (sessile). Flowers are arranged singly in two to fourteen leaf axils near the ends of branchlets, with each flower borne on a stalk 0.5–1 mm long. The sepals are light green and form a tube 2–3 mm long with two lobes: the lower lobe is 1–1.5 mm long and about 2 mm wide, while the upper lobe is 2–3 mm long and 3–3.5 mm wide. Petals are 15–20 mm long, in shades of white, pale blue, pale violet, or purplish white with red-brown spots or purple streaks inside the structure. The petals fuse to form a tube 7–10 mm long. The lower petal lip has three lobes: the central lobe is spatula-shaped, 6–10 mm long and 4.5–9 mm wide, while the two side lobes are 5.5–7 mm long and 2.5–3 mm wide. The upper petal lip has two broadly egg-shaped lobes 4–6 mm long and about 6 mm wide. This species, commonly called tall mintbush, grows in heath and woodland, with a distribution that extends from the lower Flinders Ranges, through the Mount Lofty Ranges, to the area south of Keith.
